Electric alarm device



Oct. 28, 1930. E, E, SCOTT ET AL 1,779,988

ELECTRIC ALARM DEVICE Filed April 30, 1928 2 Sheets-Sheet l 2% 1% lug} 3 gnvenl'm Oct. 28, 1930, E, SCOTT ET AL 1,779,988

ELECTRIC ALARM DEVICE Filed April 50, 1928 2 Sheets-Sheet 2 Patented Oct. 28, 1930 UNITED STATES PATENT OFFICE ERNEST E. SCOTT LAND ELMER H. BRIDENBAUGH, OF DENVER, COLORADO, ASSIGNORS TO THE ELECTRIC ALARM CO., INC., OF DENVER, COLORADO, A CORPORATION OF COLORADO ELECTRIC ALARM DEVICE Application filed April 30,

This invention relates to improvements in automatic alarms and has reference more particularly to an alarm mechanism which can be applied to automobiles and which will automatically sound an alarm whenever the tions and in which case they may even circumvent the ordinary automobile looks so that the automobile can be removed under its own power.

7 It is a further object of this invention to produce an automatic signal that will be adapted for universal use and which, in addition to being applied to automobiles can also be used for the protection of houses, garages, stores or any other building where it is desirable to have a signal that will operate whenever an unauthorized person attempts to enter the building. l

V The above and other objects which will become apparent as the description proceeds,

"" are attained by means of an apparatus which,

briefly described, consists of a spring motor that is held in inoperative position by means of a detent which will be released by the action of an electromagnet whenever the device is subjected to vibration. After the motor has been released, it will be permitted to rotate a predetermined amount and during this rotation a mechanism operated by the motor will open and close a switch which can be attached to an automobile horn or in any other suitable signal. If the disturbance has ceased when the device has operated for the predetermined time, it will remain silent but will immediately resume its operation whenever it is again disturbed.

Having thus briefly described the invention, the same will now be described in detail and reference for this purpose will be had to the accompanying drawings in which 1928. Serial No. 274,136.

the preferred embodiment thereof has been il lustrated and in which:

Fig. 1 is a side elevation of the improved signal showing the same within a casing from which the cover has been removed;

Fig. 2 is a view loo-king in the direction of arrow 2, in Fig. 1, showing one edge of the apparatus, the casing having been removed;

Fig. 3 is a view similar to that shown in Fig. 2, mt looking in the direction of arrow 3, Fig. 1;

Fig. 4 is a view of the opposite side from that shown in Fig. 1, the casing having been removed Fig. 5 is a section taken on line 5-5, Figs. 1 and at; and- Fig. 6 is a diagrammatic representation of the apparatus.

In the drawings numeral 1 represents a casing in which the apparatus is enclosed. This casing has sides 2 and 3 to which reference will be made hereinafter but as this casing merely-forms a housing for the mechanism it will not be described in detail.

The mechanism to which this invention relates comprises two members 1 and 5, of insulating material such as hard rubber or a phenolic condensation product. Attached to opposite sides of members 4 and 5 are metal frames 6 and 7, which are alike in size and shape except for this, that frame 7 has a projection 8 (Fig. 1) which forms a support for the pivot 9 on which is mounted a bell crank lever having arms 10 and 11, whose function and mode of operation will hereinafter be described. Frames 6 and 7 are connectedto each other and to the insulating members 1 and 5 by means of screws 12 and 13. A third frame member 1a is secured to frame 7 by means of screws 15 and spacers 16. An arbor 17 extends through all three frames 6, 7

and 161 and is 'ournalled in bearin s 18 one endof this arbor has a threaded portion 19 to which a winding key 20 is attached. The other end of arbor 19 has secured to it a ratchet wheel 21 with which a pawl 22-coopcrates, a spring 23 keeps the pawl in engagement with the ratchet wheel. Mounted on arbor 19 between frame members 7 and 14 is a spring housing 24 containing a sprin 25 of the type ordinarily employed in connection with clock mechanisms, one end of this spring attached to the casing at 26 and the other end issecured to the shaft by means of a pin. 7 27. hen spring is tensioned, it tends to rotate the casing 24 in the direction of the arrow 1n Fig; 6.. Casing 24 l1asone. side provlded with teeth 28 that engage with the pin- 'ion 29. on shaft 30. This shaft is journalled lGI frame. membe 6 an H and ,p sses z'i ll hfi liopfill g 1 a e Securecli shaft 30 are a ratchet wheel 31 and a gear wheel 32. Located adjacent the ratchet wheel 31, is a'member having two arms 33 that are nonrotatably. secured to" shaft 30. A lever 34 has two angularly, related arms 35-and 36 and is provided'with a slot- 37 through which the pivot pin 38 extends- A lug 39 extendsfrom lever 34 and to the outer 7 40 is connected; theotherend of th1s spring is'anchored to pin 41. A stop 42 is secured to frame member 7 and serves to limitthe end of this projection one end of coil spring rotation of lever 42 about the pivot 38. I The tially parallel with the arm ,36 and with the axis of slot 37. 1 The upperend of arm 36 has an integral lug 44 to which the lower end of spring 45 is attached. The spring 40,, nor- 'mally holds the lever 34in such a position that the upper end of arm 36 will beengaged by the ar'ms 33 and to form astop for the latter.

-' Secured, to the insulating' member 5 is a solenoid 46 with which is associated -a: co're j 747i Secured to the outer end ,of core-.47 "is.

a metal strapl48 whose end is provided with 'a-slot 49 through which-the end5O of arm 35 extends. When theelectromagnet or. solenoid is energized by an electric current, the core47 will'b'e moved towards theri'ght (Fig: 1) and this will rotate lever 34 about its pivot ease as to removethe upper end of arm 36 g from in front of the arm: 33 andthereby'permit shaft 30 to be rotated by the' spring 25.

"When the has been released-shaft 30 and ratchet wheel 31will rotate through one hundred eighty degrees when-theother arm 33 will engage t-he;e1'1dof"leveri36. -A pawl haying 'angularly related arms 10 and 11 is pivoted atI9and hasthe'end of arm'10pro, ,vided withla tooth 51- which engages with the teeth on 'the ratchet wheel in 'themai'ineri .1 shown in'Fig. 1. The free end of arm 11 has a roller 52 that is engaged by ithe'spring 53 whose upper'end is securedtothebracket 54.

Spring 53 tends torotate the pawl in" such a "direction thatthe tooth 51am always rest 'againstthe periphery of wheel 31'. WVheu ratchet Wheel3l rotates the a'wl pivoted at V 9, will oscillate and vibrate thespring 53, "whose carries a contact '55 which will t e by; be i i tii engageme t. wit t stationary Contact on thebracket 57 tacts 55 and 56 form a signal control switch to which reference will be made hereinafter. Gear wheel 32 meshes with a pinion 58 on shaft 59 which also carries a large gear 60 that in turn engages a pinion 61 on shaft 62 to which the disk 63 is attached. G ears 32, 58 60 and 61 -form a train which act as a retarder for'limiting the speedof rotation of shaft 30. 2 E e. .s0leneid.01'. electremagnets46 chasrone end. of its energizingrofl: groundectat 64 and the other end connected tothe hracket 65 bymeans of a strip 66 of conducting material. Bracket 65 has a base 67 and a parallel end or top paIrt-68andais fastened securely to the insulating iock 4 by mea-ns of screws 60. Apivotfmis securedto'ibas'e 67 and a pointed screw 71isthreadedlyconnected with the end '68 andIhel'd against rotation by means a 1 nut 7 2. iri blockf 3 is mounted between the pivots-70 and 71 and thi's'has securedtoita spring 74 to which is connected a Weight or inertia member." can moved along this s'priiig'and is held in a-djusted position by me ans of a 'screw 76f The free end .of-

.spring174 carriesa Contact 77 that is normally By means of the screw 81 1the parts can be so I adjusted,that'whentlie device is undisturbed; contacts '2"? and 78 will besepar atedy but when the device is disturbed contacts 7T andl78 will is-connecte'd to one terminalof the battery 82 wh'ose'other terminal is grounded at 83 and therefore whenever contacts 77 and 7 8 come togethcrQaneIectriC current will flow from FromFig. 6;it.will be seen that bracket 79" ahetaaeey through the spring 74' and conductor 66 to 'the solenoidi coil and" to ground 64 thereby energizing the electroinagnet and releasing arm 33 seas to permit shaft 30 to rotate in the, manner above explained. -As

soon as 'a'rnr33' has been released; spring 40 will movelever- 34 upwardly to the limit of "the slot 3'Z'andfthereby' bring; the upper end of spring 45 intocontact with the under surfa'ce-ofspring 7 4 and ,hol'd-thelatter from flexing andthereby prevent-the reestablish ment of electrical connection: between conmast? farid.-78. .untilthe, otheraarm 33. has been rot-atedi-nto. such a position that it engages the end of'lever36and moves it downwardlyagainst theaction; of spring 4O t0;the resi t enshown nis- 6-; m F ei w also appear. that bracket54 is connected with the Iungrounded terminal of the battery by .n 1 eans fofconductors .84 and 85 and that a .JleLlgqrn. 7,.that fjg ol ii a .88, w n their-at chet; wheel 3llis;rotate d con tacts 55 and I' 56 wil be .m redi 0 'e tect and. epa a d.

li e ebii ltaet y.makesaeelbrsa ies;th

conductor 86 connectsbracketv a sig current to the horn 87 which will therefore emit a series of sounds. If the initial disturbance ceases the shaft 30 will make onehalf a revolution only and will then come to rest, but if the device is disturbed when arm 33 has engaged the upper end of lever 36, the vibrations will cause the theft protective switchcontacts 77 and 78 to again come into contact and as soon as this occurs, the electromagnet will function and remove the stop and thereby release the arms 33 so that the parts will function and repeat the alarm.

Although this signal is primarily intended for use on automobiles, it is equally well adapted for use as a burglar alarm for buildings and if attached to a safe will sound an alarm if the latter is disturbed.

In the embodiment illustrated, the device is operated by a spring motor but it may be operated by any other form of motor and especially by means of an electric motor, and the specific motor shown should therefore be considered as illustrative of means only.

Having described the invention what is claimed as new is:

1. A theft alarm device comprising, in combination, a supporting frame, a spring motor carried by the frame, said motor having a gear wheel, a shaft mounted for rotation in the frame, a gear carried by the shaft, said gear being in mesh with the gear on the motor, a signal control switch, means for opening and for closing the signal control switch when the shaft rotates a radial arm carried by the shaft, a pivot pin secured to the frame, a stop lever provided with an elongated opening through which the pivot pin extends, one end of said lever when in one position lying in the path of the arm and adapted to be engaged thereby to form a stop for holding the shaft against rotation whereby the signal control switch will be held against movement, a stop carried by the frame for limiting the movement of the lever in one direction, a spring having one end secured to the lever at one side of the opening and the other end secured to the frame at a point located between the pivot point and the end of the lever whereby a force component is produced which tends to move the lever in the direction of its length and a torque is produced which tends to rotate the lever about its pivot into engagement with the stop, means comprising an electromagnet and an armature for moving the lever to inoperative position, a theft protective switch in series with the magnet, and a spring secured to one end of the stop lever and adapted to engage the theft protective switch to hold the latter in open position while the shaft is rotated.

2. A theft alarm device comprising, in combination, a supporting frame, a spring motor carried by the frame, said motor having a gear wheel, a shaft mounted for rotation in the frame, a gear carried by the shaft, said gear being in mesh with the gear on the motor, a signal control switch, means for opening and closing the signal control switch when the shaft rotates, said means including a cam member carried by the shaft, a radial arm carried by the shaft, a pivot pin secured to the frame, a stop lever provided with an elongated opening through which the pivot pin extends, one end of said lever when in one position lying in the path of the arm and adapted to be engaged thereby to form a stop for holding the shaft against rotation whereby the signal control switch will be held against movement, a stop carried by the frame for limiting the movement of the lever in one direction, a spring having one end secured to the lever at one side of the opening and the other end secured to the frame at a point located between the pivot point and the end of the lever whereby a force component is produced which tends to move the lever in the direction of its length and a torque is produced which tends to rotate the lever about its pivot into engagement with the stop, means comprising an electromagnet and an armature for moving the lever to inoperative position, a theft protective switch in series with the magnet, and a spring secured to one end of the stop lever and adapted to engage the theft protective switch to hold the latter in open position while the shaft is rotated.

In testimony whereof we afliX our signatures.

ERNEST E. SCOTT. ELMER H. BRIDENBAUGH. 

